Radix Salviae Miltiorrhizae (Danshen) is a herbal remedy that is part of many TCM herbal mixtures. Allegedly, Danshen has been used in clinical practice for over 2000 years.
But is it effective?
The aim of this systematic review was to evaluate the current available evidence of Danshen for the treatment of cancer. English and Chinese electronic databases were searched from PubMed, the Cochrane Library, EMBASE, and the China National Knowledge Infrastructure (CNKI), VIP database, Wanfang database until September 2018. The methodological quality of the included studies was evaluated by using the method of Cochrane system.
Thirteen RCTs with 1045 participants were identified. The studies investigated the lung cancer (n = 5), leukemia (n = 3), liver cancer (n = 3), breast or colon cancer (n = 1), and gastric cancer (n = 1). A total of 83 traditional Chinese medicines were used in all prescriptions and there were three different dosage forms. The meta-analysis suggested that Danshen formulae had a significant effect on RR (response rate) (OR 2.38, 95% CI 1.66-3.42), 1-year survival (OR 1.70 95% CI 1.22-2.36), 3-year survival (OR 2.78, 95% CI 1.62-4.78), and 5-year survival (OR 8.45, 95% CI 2.53-28.27).
The authors concluded that the current research results showed that Danshen formulae combined with chemotherapy for cancer treatment was better than conventional drug treatment plan alone.
I am getting a little tired of discussing systematic reviews of so-called alternative medicine (SCAM) that are little more than promotion, free of good science. But, because such articles do seriously endanger the life of many patients, I do nevertheless succumb occasionally. So here are a few points to explain why the conclusions of the Chinese authors are nonsense:
- Even though the authors claim the trials included in their review were of high quality, most were, in fact, flimsy.
- The trials used no less than 83 different herbal mixtures of dubious quality containing Danshen. It is therefore not possible to define which mixture worked and which did not.
- There is no detailed discussion of the adverse effects and no mention of possible herb-drug interactions.
- There seemed to be a sizable publication bias hidden in the data.
- All the eligible studies were conducted in China, and we know that such trials are unreliable to say the least.
- Only four articles were published in English which means those of us who cannot read Chinese are unable to check the correctness of the data extraction of the review authors.
I know it sounds terribly chauvinistic, but I do truly believe that we should simply ignore Chinese articles, if they have defects that set our alarm bells ringing – if not, we are likely to do a significant disservice to healthcare and progress.